When your microwave is done with its food, it generally beeps… and beeps… and beeps. Though you definitely want to know when your frozen burrito is edible, if you get to it right when it wants, things can get quite annoying. Tim Gremalm decided to do something about it, and replaced the buzzer in his appliance with an Arduino Nano, an amplifier, and small speaker.
His initial speaker/amplifier combination wasn’t loud enough so he replaced it with more appropriate options. After this hack, he now has something that can play a more pleasing tone—in his case, the Windows XP startup sound—and do so only once!
You can see more of this project on Gremalm’s page, as well as check out his code here or this Arduino program that inspired his code. It’s a neat hack, and a great example of what can be done with an Arduino, but you probably shouldn’t mod your microwave unless you really know what you’re doing!